Drilling string protector



June 30, 1942. T. A. cRElGHToN DRILLING STRING` PROTECTOR 2 Sheets-SheefI l Filed NOV. 15, 1939 @Bf @MM y HKS ffl/a@ v June 3o, 1942. T. A. CREIGHTQN 2,288,124

DRILLING STRING PROTECTOR Filed Nov. 15. 1959 2 sheets-sheet 2 l @www Patented June 30, 1942 DRILLING STRING PROTECTOR Thomas A. Creighton, Long Beach, Calif., assi'gnl or of one-half to Martha H. Wright, Los Angeles, Calif.

Application November 13, 1939, Serial No. 303,955 3 claims. (o1. 30s-g4) This invention relates to rotary well drilling equipment and relates more particularly to protectors for protecting rotary Well drilling strings against` excessive Wear. A general object of this invention is to provide practical, dependable and long Wearing drilling string protectors.

Oil Wells and gas Wells are being drilled to greatY depths bythe rotary method of drilling and With the present day practice it is customary to rotate the drilling string rapidly and to drill as far ahead of the set casing as possible before setting another casing. When the drilling tools are operated in this manner a substantial portion of the drilling string is rotating at a high speed in the open, uncased part of the Well and the tool joints and upset end portions of the pipe sections are subjected to excessive Wear through contact with the side Wall of the bore. The tool joints and the upset end parts of the pipe rapidly Wear out of round, requiring expensive replacements and this Wear sometimes causes failure of the string through unbalanced stresses at the couplings. Rubber protectors are often provided on the portion of the drilling string that operates in the cased part of the Well to protect both the Well casing and the drill pipe against Wear, but such rubber protectors are incapable of withstanding the hard usage to which they would be subjected in the open uncased part of the Well.

Another object of this invention is to provide drilling string protectors for application to the portion of the drilling string operating in the open uncased part of the Well that fully protect the tool joints and the pipe against wear through contact With the Well wall.

Another object of this invention is to provide protectors of the character mentioned embodying hard or hardened wear Ataking elements for engaging the wall of the Well to protect the bodies of the devices against direct engagement with the Well wall.

Another object of this invention is to provide drilling string protectors of the character mentioned that are easily and quickly secured to the drilling string in a dependable manner and without injuring or weakening the string.v

Another object of this invention is to provide protectors of the character mentioned in Which the Wear taking parts of hard material l'may be easily and quickly replaced when Worn.

Another object of this invention is to'p'rovide drilling string protectors that may be readily secured to previously assembled portions or strands of the string.

A further objectv of this invention is to provide drilling string protecting means that may be embodied inor applied tothe tool joint sections of the drilling string making it unnecessary to secure protective partsdirectly on the pipe.

A Ystill furtherrobject'of this invention is to provide drilling string protective means that are inexpensive'to manufacture and to vrapply to the drilling string The various objects vandieatures of my invention `'will ibe fully understood from the following detailed description of typical preferred forms and applications of the invention, throughout which description reference is made to the accompanying drawings, in which:

Fig. l is a side elevation of aportion of arotary well drilling string showing one form of protector ofthe invention secured thereon. Fig. 2 is an enlarged side elevation of a portion of the drill pipe with the protector of Fig. 1 in longitudinal cross section. Fig. 3 is an enlarged fragmentary transverse detailed sectional view vtaken as indicated by line 3--3 on 'Fig- *1. Fig. 4 is a side elevationof anotherV form of protector of the invention secured to a drill pipe. Fig. 5 is an enlarged longitudinal detailed sectional view of the protector of Fig. 4in position on the pipe, showingthe pipe in side elevation. Fig 6 is an enlarged transverse detailed sectional view taken as indicated 'by line 6 6 on'Fig. 4. Figs. '7 and 8 are fragmentary transverse sectional views 'illustratingalternative forms of Wear taking elements that may beapplied to the protectorsil- `lustrated in Figs. 1 and 4. Fig. 9 is a side elevation of a portion offa rotary well drilling string showing a protective means of the invention embodied in a tool joint of the string. Fig. 10 is an enlarged fragmentary side elevation of the drilling string vshown 'in Fig. 9 with the vupper portion of the tool joint in longitudinal cross section. Fig. 11 is a fragmentary transverse detailed sectional vieW taken as indicated 'by line li-II on Fig. 10 and Figs. 12 and 13 are views similar to Fig. 11 illustrating'alternative forms of hard Wear taking 'elements that may be embodied inthe structure of Figs.'9 to 11.

The form of the `invention'illustrated infFigs. l, .2 and 3 of the drawings may be said to comprise, generally, 'a sectionalbody l0 or'application to the drilling string S, means Il vfor securing th'e body I0 to the string S and hard VWear `taking elements I2 on the body l0 for contacting the side Wall of the Well'bore.

In accordance Withrthe invention the lbody I0 of the 'protector shown in Figs. 1, 2 and 3, issectional so that it may be readily assembled about the string S or about a section of pipe P of a made-up stand of the string S. The body I is preferably constructed of steel or other metal or metals. In the preferred construction the body I0 is an elongate tubular member longitudinally divided into two halves or sections A and B. The body I is proportioned to snugly t about the pipe P, that is, the opening in the tubular body rather accurately receives the pipe. The longitudinal edges I3 of the body sections A and B are preferably flat and radial to evenly abut. It is preferred to proportion the body ID so that its external diameter is not greater than the external diameter of the tool joints J or the other couplings of the string S so that the protector does not interfere with the circulation of fluid through the well. The upper and lower outer corners of the body Ill may be bevelled off, as illustrated.

The means II for securing the body I0 to the pipe P is such that the body may be quickly secured to the pipe after the string S or the stand of the string S has been made up. The securing means I I includes one or more pockets or notches I4 in the ends of the sections A and B. I n the case illustrated there are circumferentially spaced notches I4 in each end of each body section A and B. The notches I4 are preferably, though not necessarily, partially cylindrical. 'Ihe means II further includes blocks or lugs I5 on the pipe P engaging in the sockets I4. The lugs I5 may be secured to the drill pipe P by welding or may be in the nature of material built up by the welding operation.

The cooperation of the lugs I5 and the notches I4 dependably holds the body I0 against both longitudinal and turning movement relative to the pipe. Following the assembling of the sections A and B about the pipe P the sections are welded together so that the body forms a single rigid unit on the pipe. Lines of welding I1 may be formed to extend along the longitudinal edges I3 of the sections A and B to join or connect the two sections. Following the welding together of the sections A and B the lugs I5 are formed or are welded to the pipe to cooperate with the notches I4. If desired, the securing means II may further include welding I8 at the ends of the body I0 securing the body to the pipe P. The welding I8 is not essential where the lugs I5 and notches I4 are employed. It is to be observed that the protector body I0 may be easily and quickly assembled about the pipe section of a previously made up stem of the drilling string.

'I'he wear taking elements I2 are secured to the body I and are formed and positioned to contact the wall of the well to protect the body I0 and, of course, the pipe and joints J, against excessive wear. The wear taking elements I2 may take various forms or shapes as will be later described. In the case illustrated in Figs. 1, 2 and 3 the elements I2 are elongate parts having outwardly converging sides. The elements I2 may be formed of any suitable wear and abrasion resisting material. The wear taking elements I2 may be formed of hardened or tempered steel, hard alloys, or the like. If desired, the outer sides of the hard elements I2 may be hard faced or provided with hard material as indicated at I9. The hard wear taking elements I2 are removably secured to the body I0 to project from the periphery of the body. A plurality of circumferentially spaced longitudinal grooves 20 is provided in the periphery of the protector body and each groove is adapted to receive an element I2. The grooves 20 extend upwardly in the body IIJ from its lower end and have upper end walls 2I spaced from the upper end of the body. The side walls 22 of the grooves 2li are outwardly convergent. The elements I2 are passed upwardly in the grooves 20 from their lower ends and the upper ends of the elements may bear against the end walls 2|. The converging sides of the elements I2 cooperating with the converging walls 22 dependably hold the elements I2 against outward displacement.

Means are provided for holding the elements VI2 against longitudinal movement and displacement. Screws 23 are threaded in radial openings 24 in the body I0 and are positioned so that their heads engage the lower ends of the elements I2. The screws 23 hold the elements I2 against downward movement in the grooves 20 and retain the elements where their upper ends engage the walls 2I. The hard wear taking elements I2 are proportioned to have their outer parts project beyond the peripheral surface of the body II) to engage the wall of the well in the event the drilling string is crooked or gyrates. These projecting portions of the elements I2 protect the body I0 against excessive wear. It will be observed that the longitudinal forces on the elements I2 resulting from the downward movement of the drilling string in the well are directly transmitted from the elements I2 to the body I0 through the engagement of the elements with the end walls 2| of the grooves 20.

In use or operation the body sections A and B are assembled about the pipe in the selected plane. The body I0 may be provided with the elements I2 either before or after the attachment of the body to the pipe P. When the body sections A and B are correctly assembled about the pipe P the welds II are made to join the sections and the lugs I5 are then applied or formed to cooperate with the notches to secure the body IE) to the pipe P. This assembling of the protector and its attachment to the pipe P does not necessitate disturbing the tool joint parts or the collars of the string or the assembled stand of the string. When the drilling string is in operation in the well, the contour of the well, the rate of rotation of the string, and other factors may tend to cause the string to wear or bear against the side wall of the well. The protectors of the invention prevent the pipe or any parts of the string S from engaging the side wall of the well and thus prevent wearing of the string. The protectors may be secured to the string in spaced adjacent relation to the tool joints J and as many protectors may be employed as believed necessary. The protectors spaced along the string in the open uncased part of the well effectively prevent the pipe from wearing against the side of the well. The wear taking elements I2 project from the surfaces of the protector bodies I0 and thus are adapted to engage against the wall of the well. The hard elements I2 serve to protect the bodies IU and to prevent excessive wearing of the bodies.

After extended use it may be desired or necessary to replace the elements I2. The screws 23 may be removed so that the elements I2 may be slid or driven from the grooves 20. New or reconditioned wear taking elements I2 of any selected material may be vinserted in the grooves 20 to recondition the protector for further use. This replacing of the elements I2 may be accomabrasion resisting material.

plished without removing the protector 'from the drilling string Sor the pipe P.

The form of the invention illustrated'in Figs. 4, and 6 may be said to comprise, generally,

a body l0a secured to the ydrillpipe P and hard wear taking elements l2a carried by the body.

The body |08 is an elongate tubular member of steel or other metal proportioned to be readily slid onto the pipe P. It is preferred to proportion the body ||la so that its external diameter is no greater than the external diameter of the tool joints of the drilling string. It is preferred to rigidly iix the body||la .to the pipe P. Welding'24 at the upper and lower ends of the body ||)a may serve to secure the body to the pipe P.`

If desired, the notches I4 and lugs I5 described above maybe employed to assist in securing the body lliEL to the pipe P. The body 10e may be secured on the pipe at any selected point.

The wear taking elements I2a are provided to engage or cooperate with the side wall of the well bore to protect the body Il!a against excessive wear. The elements |28 are formed of a hard In the particular construction illustrated in Figs. 4, 5 and 6 the wear taking elements |2a are elongate cylindrical parts. The elements |2a are arranged in longitudinal grooves in the body Illa. The walls of the grooves 25 extend for more than 180 so that the elements |23 are dependably held against .outward displacement.

upwardly from the lower end of the body |321v The grooves 25 extend Vmouths or outer sides of the grooves 25 to project from the periphery of the body lila. The wear taking elements |2a arranged as just described -may rotate about -their individual axes through contact with the wall of the well.

YIn employing the protectors illustrated in Figs. 4,-5 and 6 of the drawings the protector bodies |||a carrying the elements VI2a -may be secured to the drilling string at Vselected spaced points to operate in the open uncased portion of the-well. When the drilling string is operating in the -well the circumferentially spaced wear taking elements |2a may engage the side wall of theY well to prevent the pipe Pand the joints and couplings of the string from wearing against the earth formation. The hard elements |2a projecting from the'periphery of the body llla protect the body against excessive wear. The elements |2a being formed of a very hard material are long wearing. After extensive use it may be found desirable or necessary to replace the elements I2a. Upon removal of the screws 21 the elements |2a may be readily removed from the grooves 25 and new or replacement elements may be arranged in the grooves.

The form of protector illustrated in Figs. 1, 2 and 3 may be provided with hard wear taking elements |'2EN Yof the `kind shown in Figs. 4, 5 and 6 and the protector illustrated in the last named gures may be provided with wear taking elements |2 of the kind shown in Figs. l, 2 and 3.

. Fig. 'l of the drawings illustrates another form of wear taking element I2b that may be employed in either of the above described protectors. The elements I2b are elongate parts constructedV of a very hard wear resisting'material. The elements |22b :are polygonal or square in transverse cross section and are adapted to be .removably'arranged in longitudinal ygrooves 28 in the protector body. The grooves 28 are partially square in'transverse cross section to cooperate with the flat sides of theelements 12b. The grooves 28V are formed and arranged so that the elements IZbfhave diagonal lines substantially radial with respectito the longitudinal axis of the protector andttwo opposite longitudinal corner portions of each element `|2b are received in a groove 28 so that the grooves serve to hold the elements against outward displacement. 'I'he elements Il."o may be held against longitudinal displacement in the same .manner as the elements I2. There is a plurality of circumferentially spaced grooves 28 provided to receive the elements i21D and the elements l2b projecting from the periphery of the protector serve to protect the protector body against excessive Wear through engagement with the wall of the well.

While I have described the wear taking elements 2, Iza and |2b as formed of hard abrasion resisting material, it maybe found desirable to form these-elements of rubber, rubber and fabric, or the like, to adapt the protectors for use under different conditions or for use in other situations.

Fig. 8 of the drawings illustrates another manner in which a protector body ||lc of the invention may be provided with hard wear taking parts. In this construction the body llic is provided with one or more rows or stripes oi hard facing 29. The hard facing 29 may extend either circumferentially or longitudinally of the body Il!c or may cover the entire surface of the body. The hard facing 29 may consist of pieces or particles or" very hard material welded to the surface of the protector body lilc and serves to protect the body against excessive Wear through engagement with the well wall.

The embodiment of the invention illustrated in Figs. 9, 10 and ll of the drawings may be said to comprise, generally, a tool joint 33 connected in a drilling string SY and hard wear taking elements |2c1 carried by the joint I0 to protect it against wear through engagement with the wall of the well. The tool joint 30 comprises a pin section 3| and a box section 32. rIhe sections 3| and 32 have threaded sockets 33 in their outer endsreceiving threaded end portions of the pipe P. The box section `32 has a tapered threaded socket 34 for receiving the tapered threaded pin 35 Yof the .pin section 3|. The sections 3| and 32 are formed with rather heavy walls to provide ample stock for carrying the threads and, therefore, are considerably larger in external' diameter than the pipe P. The sections 3| and 32 may be of standard or conventional design except that one v.or both of the sections may be considerably longer than usual.

The hard wear taking elements I2d may be provided on either one or both of the tool joint sections 3| and 32. In the simple case illustrated the elements |2"1 are provided on the pin section 3| which constitutes the upper section of the joint 33 land the box section 32 is of typical construction. The elements |22d may -be varied in shape. In the construction shown in Figs. 9, 10 and 11 the elements |2d are elongate parts removably arranged in circumferentially spaced grooves 36 in the section 3|. The elements I2d are I-shaped in transverse cross section and the grooves 36 are of corresponding shape. The grooves 36 may extend downwardly from the upper end of the section 3| to terminate in upwardly facing end walls 31. The elements l2d are passed downwardly into the grooves 36 so that their lower ends may bear on the walls 31. As best illustrated in Fig. 11 the inner iianges 80 of the elements I2d cooperate with the walls of the grooves 36 to hold the elements |2d against outward displacement. Set screws 38 are threaded in openings in the upper portion of the section 3| and engage the upper ends of the elements I2d to hold the elements against upward displacement. The wear taking elements 12d extend from the outer sides of the grooves 36 to project from the periphery of the joint section 3|.

In the use or operation of the construction illustrated in Figs. 9, l and ll, the tool joint 30 may be connected in the drilling string S in the usual manner to couple the adjacent ends of two stands of pipe. The joint 30 provided with the wear taking parts |2d and similar joints 30 are provided at points where they will operate in the open uncased portion of the well. During the drilling operations the circumferentially spaced elements I2d projecting from the periphery of the section 3| may contact the side wall of the well, if the string tends to buckle or gyrate to protect the joint 30 and the other parts of the string against wear. The elements l2d effectively protect the tool joint against wear. After extensive use it may be found desirable to replace the elements |2d. Upon removing the screws 33 the worn elements |2d may be readily removed from the grooves 36 and replacement elements inserted in the grooves.

Figs. l2 and 13 of the drawings illustrate hard wear taking elements l2e and lf, respectively, that may be embodied in the tool joint 3U. The wear taking elements I2e are polygonal or square in transverse cross section and are formed of a hard abrasion resisting material. Where the elements I2e are employed in the section 3|e of the joint is provided with a plurality of circumferentially spaced grooves 35e shaped to receive the polygonal elements. The grooves 36e are partially square in transverse cross section and the engagement of their walls with the elements I2e holds the elements against outward displacement. The elements I2e project from the mouths of the grooves 36e to form Wear taking ribs or ridges on the periphery of the section 3 le.

The wear taking elements l2 of Fig. 13 are elongate parts having outwardly diverging sides 4D. The joint section 3|f for carrying the elements |2f is provided with spaced longitudinal grooves 4| whose side walls 42 are outwardly convergent. The elements I2f are inserted in the ends of the grooves 4| and the engagement of their sides with the convergent walls 42 holds the elements against displacement. The elements |2f are proportioned to protrude from the grooves 4| so that the elements form longitudinally extending wear taking ridges on the periphery of the joint section 3|f. The wear taking elements l2e and |2f may be removably held in their respective grooves in the same manner as the elements |2d.

In certain uses of the protectors the elements |2d, l2"l and |2f may be replaced by similar elements formed of rubber, synthetic rubber, rubber and fabric, etc., secured in their respective grooves. j

Having described only typical preferred forms and applications of my invention I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to -myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

l. A protector for a rotary well drilling string comprised of threadedly connected parts, the protector including a body threaded at its opposite ends to be connected -between two threaded parts of the string, the body having spaced longitudinal grooves of polygonal transverse cross section extending from one end thereof, the ends of the grooves at said end of the bodt7 being open when the body is connected between said parts of the string, hard wear resisting elements of polygonal transverse cross section removably inserted into said open ends of the grooves to project from the exterior of the body, the sides of the polygonal elements cooperating with the walls of the grooves to hold the elements against lateral displacement, and screws threaded into said end of the body and extending into the grooves to removably retain the elements therein.

2. A protector for a rotary well drilling string made up of threadedly connected parts, the protector comprising a one piece tubular body threaded at its ends to be secured between two parts of the string to extend longitudinally of the string and to form an interposed part thereof, the body having external grooves extending longitudinally from one end thereof, the ends of the grooves at said end of the body being clear and open when the body is secured between said parts of the string, elements of hard wear resisting material passed into the grooves from said end of the body and projecting from the exterior of the body, and means on the body for retaining the elements in the grooves and removable to allow removal of the elements without necessitating detachment of the body from the adjacent string parts.

3. A tool joint for connecting two lengths of well drill pipe comprising threadedly engaged pin and box sections threaded at their outer ends for connection with the drill pipe, said sections each being integral and of greater external diameter than the drill pipe, at least one of said sections having spaced longitudinal grooves in its exterior extending from its outer end, the grooves having under cut side Walls and closed inner ends, elements of hard wear resisting material inserted into the grooves from their outer ends and anged to conform to the side walls of the grooves to be held against lateral displacement thereby, and screws threaded into said section and, engaging the outer ends of the elements to retain the elements in the grooves, said elements being insertable and removable without disconnecting the pipe from said section when the screws are removed.

THOMAS A. CREIGHTON. 

